Question: Consider the equation $1.5x+4.5y=18$. 1. If we graph the equation, what is the slope of the graph?
1. **State the problem:** We are given the linear equation $$1.5x + 4.5y = 18$$ and asked to find the slope of its graph.
2. **Rewrite the equation in slope-intercept form:** The slope-intercept form is $$y = mx + b$$ where $$m$$ is the slope.
3. **Isolate $$y$$:**
$$1.5x + 4.5y = 18$$
Subtract $$1.5x$$ from both sides:
$$4.5y = 18 - 1.5x$$
4. **Divide both sides by $$4.5$$ to solve for $$y$$:**
$$y = \frac{18 - 1.5x}{4.5}$$
Use the property of fractions:
$$y = \frac{18}{4.5} - \frac{1.5x}{4.5}$$
Simplify each term:
$$\frac{18}{4.5} = 4$$ and $$\frac{1.5}{4.5} = \frac{\cancel{1.5}}{\cancel{4.5}} = \frac{1}{3}$$
So,
$$y = 4 - \frac{1}{3}x$$
5. **Rewrite in slope-intercept form:**
$$y = -\frac{1}{3}x + 4$$
6. **Identify the slope:** The slope $$m$$ is the coefficient of $$x$$, which is $$-\frac{1}{3}$$.
**Final answer:** The slope of the graph is $$-\frac{1}{3}$$.